1. Field of Invention
This invention relates to a probe forming a part of a surgical suction system for the removal of debris from a surgical site, and, more particularly, to such a probe including an internal filter for removing and holding larger pieces of such debris from waste slurry flowing through the probe.
2. Description of the Related Art
The patent literature describes a number of suction probes for use in surgical suction systems to remove debris from a surgical site, with the probe including or being associated with an internal filter for removing and holding the larger pieces of waste slurry flowing through the probe. Such a suction probe has an inlet large enough to permit the entrance of debris particles too large to be handled reliably through the remaining portion of the suction system, such as the conduit leading to a suction source. These particles are trapped within the internal filter. Each such suction probe is separable into two pieces so that the internal filter can be cleaned or replaced as it becomes clogged or as tissue samples are needed, for example, for pathology.
For example, U.S. Pat. No. 4,468,217 to Kuzmick et al. describes a surgical suction tip including an inner removable filter device. The housing includes a suction opening at one end and a filter receiving handle formed as a sleeve at the other end; the inner removable filter device is connected in the filter receiving handle by a quick connect-disconnect means; the housing tapers to increase in size from its suction opening to the filter device. A seal is located between the housing and the filter device. Within this device, filtration occurs through a cylindrical filter having a number of holes between a chamber within the cylindrical filter and a chamber within the device but outside the cylindrical filter. The chamber within the cylindrical chamber is in fluid communication with a suction source, while the chamber outside the cylindrical chamber is in fluid communication with an aperture at the distal end of the probe tip, through which debris is sucked.
U.S. Pat. No. 5,779,649 to Herbert describes a surgical suction wand comprising a generally tubular body with a hollow tip at one end thereof, a cap releasably closing the other end of the tubular body, and a filter member within the body and joinable to the under surface of the cap. The filter member is wedge-shaped, having a number of holes through which debris is sucked into a space within the filter. The filter member is removed, along with the cap, and is cleaned and returned to the interior of the tubular body as required. The cap snaps in place on the tubular body, with a ridge extending around an end of the tubular body snapping in place within a groove extending around an end of the cap, and with a tab being provided to ease the disengagement of the snap fit.
U.S. Pat. No. 5,630,939 to Bulard et al. describes a filter assembly for elective use in conjunction with a surgical evacuation system. The filter assembly includes a filter housing having a head portion and a body portion with a through passageway extending therebetween defining a filter receiving chamber. The head portion is connectable to an aspirator tip and the body portion is connectable to a flexible suction conduit. A filter element is disposed within the filter receiving chamber of the filter housing. The filter element includes a head member having a fluid flow passageway extending therethrough, a fluid impermeable base member spatially disposed from the head member, and a fluid permeable body member disposed between the head member. The head member and the body member are joined by a cylindrical surface having an O-ring seal, so that the head member and the body member are separated by twisting and sliding to install, remove, or replace the filter element.
U.S. Pat. No. 5,766,134 to Lisak et al. describes a collector unit for collecting tissue or bone from a dental patient during a dental implant procedure. The collector unit includes a cover member, a filter support member, a filter medium, and a gasket support member. The support member is mountable within the cover member with the gasket member positioned therebetween to form the unit. The support member has a pair of spaced-apart, opposed filter support arms for removably supporting a substantially flat section of filter medium, so that the filter medium overlays an input passageway through which liquid is drawn. After the unit is disassembled, the filter medium is removable from the supporting structure so that it can be positioned in a flat orientation to facilitate the removal of bone or tissue specimens therefrom. Once removed, the filter medium cannot be reattached to the supporting structure.
U.S. Pat. No. 5,807,353 to Schmitz describes an aspiration device for separating liquid content of a body fluid and irrigation fluid, if any, from solid material. The device includes an integrally formed housing and an integrally-formed separating element, which is detachably inter-connectable to the housing. The housing includes a proximal segment for defining a hollow space to receive part of the separating element. The separating element includes a filter element for separating the liquid content of the body fluid from the solid matter and for collecting the solid matter in the interior of the filter element. The separating element further includes an end connector for interlocking the separating element with the housing, and an egress tube for conveying the liquid content outside the aspiration device. The filter element is a slotted cylinder, with debris being sucked through and end of the cylinder, and with liquid being further sucked outward through the slots while solid material remains within the cylinder. The device is cleaned, or collected material is removed, by twisting a threaded end connector so that it is disengaged from the proximal end of the housing. The separating element is then removed, so that the filter can be cleaned or replaced.
Each of the patents described above discloses a suction device having an internal filter which can be cleaned or removed and replaced only when the suction device is taken apart to reveal the internal filter. What is needed is a method providing for cleaning the filter without disassembling the device and without a need to wipe the filter. The process of disassembly, wiping, and reassembly is relatively time consuming, and must often be performed several times during a surgical procedure. This process results in a number of pieces of the suction device and the filter, which must be separately handled and reassembled. A lack of the suction process during this process can also interrupt other surgical procedures taking place. Furthermore, what is needed is an ability to hold trapped debris so that it is unnecessary to handle such debris during a surgical procedure.
A number of U.S. patents describe surgical suction probes without internal filters. For such a device to be used reliably to remove debris from a surgical site, solid fragments the tip aperture must be small enough to prevent the aspiration of particles from the waste slurry which are large enough to clog the conduit extending between the suction probe and a vacuum source generating the suction, the vacuum source itself, or a fluid separation device associated with the vacuum source. On the other hand, fragments too large to pass through the aperture may be held externally at the aperture or allowed to fall back into the surgical site. What is needed is a mechanism allowing such fragments to be trapped and held within the suction probe, without being allowed to flow along the conduit to the vacuum source, and without being redeposited at the surgical site. This need is apparent when the suction probe is used to clean debris from the site of an orthopaedic procedure, in which bone fragments of various sizes are produced.
Examples of such patents include U.S. Pat. No. 5,520,668 to Greff et al., which describes a surgical suction system and method including a source of suction and a conduit having a distal end and a proximal end. At its distal end, the conduit has a diameter not greater than about ⅝ inch to provide limited access to the surgical site and an inside diameter not less that about ¼ inch to accommodate the bone fragments in the waste slurry. A coupling is provided for connecting the proximal end of the conduit to the suction source in order to provide suction at the distal end of the conduit at a velocity not less than about ninety miles an hour. A fluid containment vessel can be connected between the conduit and the source of suction to provide a liquid trap for the waste slurry passing along the conduit.
U.S. Pat. No. 4,878,900 to Sundt describes a probe and suction device for use during surgery, including an elongated tubular handle adapted for connection to a source of suction and a separable elongated tubular probe and suction member. It includes a suction regulating orifice in the handle and is characterized by a positive snap-on rotatable connection between the handle and the probe and suction member. The distal end of the probe and suction member is blunted to avoid tissue damage.
U.S. Pat. No. 5,123,840 to Nates describes a suction probe including a controllable suction port, which the individual using the probe can partly or totally cover with a finger to control the level of suction available at the probe tip, through which debris is removed.
U.S. Pat. No. 4,068,664 to Sharp et al. describes a surgical suction wand assembly including a modular suction wand having a hollow suction tip, along which a number of laterally disposed external apertures extend. The tip may be provided with an elongated interiorly disposed tube simultaneously providing for effective aspiration of small amounts of liquid as well as a large suction area for efficiently aspirating larger volumes with minimal opportunity for obstruction. While the apertures in the suction tip provide a filter preventing the aspiration of larger fragments, such fragments may be expected either to remain held in place externally on the suction tip as it is used, or to fall back into the surgical site. Thus, what is needed is a mechanism for removing such fragments from these apertures and for safely holding them as the surgical wand is used.